Update WebTask in chromium c++ style

content/shell/renderer/test_runner/WebTask.cpp

-// Copyright 2013 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "content/shell/renderer/test_runner/WebTask.h"
-
-#include <algorithm>
-#include "third_party/WebKit/public/web/WebKit.h"
-
-namespace content {
-
-WebTask::WebTask(WebTaskList* list)
-    : m_taskList(list)
-{
-    m_taskList->registerTask(this);
-}
-
-WebTask::~WebTask()
-{
-    if (m_taskList)
-        m_taskList->unregisterTask(this);
-}
-
-WebTaskList::WebTaskList()
-{
-}
-
-WebTaskList::~WebTaskList()
-{
-    revokeAll();
-}
-
-void WebTaskList::registerTask(WebTask* task)
-{
-    m_tasks.push_back(task);
-}
-
-void WebTaskList::unregisterTask(WebTask* task)
-{
-    std::vector<WebTask*>::iterator iter = std::find(m_tasks.begin(), m_tasks.end(), task);
-    if (iter != m_tasks.end())
-        m_tasks.erase(iter);
-}
-
-void WebTaskList::revokeAll()
-{
-    while (!m_tasks.empty())
-        m_tasks[0]->cancel();
-}
-
-}  // namespace content